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COF^fRIGKT DEPOSm 



SHOP SKETCHING 



A COURSE OF PROBLEMS FOR 
MECHANICAL DRAWING STUDENTS 

By RALPH F. WINDOES 

Supervisor of Manual Arts, Rock Island, 111. Author of "Architectural Drawing for Secondary 
Schools," "Cedar Chests: How to Make Them," "Stories of the Industries," etc. 




THE BRUCE PUBLISHING COMPANY 
MILWAUKEE, WIS. 



5 5^ 



Copyright 1919, by 
The Bruce Publishing Company 



M 1 1 f9fg 

©CI.A529164 



CONTENTS 

Page 

Preface --.-___ 5 

General Statement ------ 7 

Problems in Sketching ----- 13 

The Perspective Protractor - - - - 26 

The Circle in Perspective - - - - 30 

Sketching on Cross Section Paper - - - 54 

Supplementary Problems - - - - 56 



PREFACE 



THE ability to rapidly make freehand sketches, 
either in perspective or orthographic, is one 
of the essential accomplishments of all good 
draftsmen. By this means they may interpret to 
persons not informed how to read working drawings. 
With this ability draftsmen are able to rapidly sketch 
some detail of a machine or a broken part too largo 
to carry to the drafting room, where a working draw- 
ing can be made from the sketch. A study of sketch- 
ing is one of the quickest means of learning how to 
read working drawings, as it does not involve ths 
r.bility to use the drafting instruments skillfully. 
These are only a few of the many advantages that 
are well known and appreciated by teachers — ad- 
vantages that have given shop sketching an important 
place in every mechanical drawing course. 

This text presents a carefully arranged and 
thoroughly tested course of problems in shop sketch- 
ing which will leave with the average student com- 
pleting it the ability to make sketches from objects; 
perspective sketches from working drawings : and the 
ability to accurately read working drawings. It 



should be given in the last half of the first year's 
work, or in the second year. Since so many students 
drop out of school after the first year, the latter part 
of that year is recommended for this work, as 
nothing can be given that has the practical ad- 
vantages of shop sketching. 

As much theory as possible has been omitted 
from this course. Technicalities concerning perspec- 
tive have been carefully explained, simplified, or left 
to a more advanced course. The one aim has been 
to impart to the student the knowledge and practice 
necessary to rapidly make clear and accurate free- 
hand shop sketches. - 

The work as arranged can be covered in one half 
year of five months when the students work forty- 
five minutes each day of the school week. This should 
take the average through plate twenty. Other plates 
have been added to supplement this work, lengthen 
the course, or to provide work for the more apt stu- 
dents. These more advanced plates will be of help 
where the course is used in normal and technical 

schools. EALPH P. WIISTDOES. 



General Statement 



Shop Sketching. The practical value of free- 
hand sketching can not be overestimated. It is not 
too much to say that nothing that can he given in an 
elementary mechanical drawing course is of more 
importance to the man who expects to advance in the 
profession, and the student just beginning his draft- 
ing course will do well to bear this fact in mind. 

Tracers and detailers — mere routine men — may 
be proficient without the abilit}' to make good, clear, 
and accurate freehand sketches, but the engineer and 
the designer must have this abilitj''. The inventor 
whose time is too valuable to spend in mechanical 
execution at the drafting board must be able to ma- 
terialize his thoughts by the means of freehand 
sketches, which will later be passed on to the drafts- 
men to execute. 

Definitions. Shop sketches may be of various 
kinds — as many kinds as there are modes of technical 
expression, though they are usually in one of two 
methods — orthographic or working sketches, and 



perspective sketches. Any one of the axonometric 
projections can be utilized — especially isometric — or 
cabinet projection may be used. As a general rule, 
sketches from objects which are to be later drawn up 
to scale in the regular manner will be made in ortho- 
graphic. Inventive sketches in either orthographic 




Figure 1 



SHOP SKETCHING 



or perspective, and sketches that are used to explain 
working drawings to the uninitiated, in perspective. 

The camera, when properly focused, shows an ob- 
ject in true perspective. Figure 1 illustrates a library 
table from a photograph, Figure 2 is a perspective of 
the same table, and Figure 3 is its orthographic pro- 
jection. The close resemblance between the photo- 
graph and the perspective is very apparent, while the 
orthographic gives the exact appearance of the top, 
front, and side views as if each were viewed alone and 
the others could not be seen. Hence each view in 
the orthographic shows but two dimensions, while the 
perspective and photograph show three. This will 
make it apparent that at least two views are neces- 
sary in orthographic projection to properly show all 
three dimensions of length, breadth, and thickness. 
To the student who has made a study of orthographic 
projection these statements will come as a review. 

As stated before, all of the problems in this course 
will be made as freehand orthographic or perspective 
sketches. 




Figure 2 
DRAViriNG MATERIALS REQUIRED. A 2 H pencil, 

a 4 H pencil, a pencil eraser, paper, drawing board, 
and thumb tacks are all the materials needed for the 
drawing work. The paper should have a rather hard 
surface as the rough surface of the ordinary drawing 
paper soils too rapidly. The plates are to be made on 
sheets measuring ll"x 15", which can be cut with- 
out waste from the standard size of 22"x 30". 

The pencils should be sharpened to long, conical 
points. 



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Figure 4 



GENERAL STATEMENT 



11 



Measuring Tools. A two-foot rule and a pair 
of calipers will be all the measuring tools actually 
needed for this course, but some additional tools will 
be of great help, especial^ when taking measurements 
of large or complicated machines and parts. These 
tools are all illustrated in Figure 4 and consist of, 
in addition to the tn^o-foot rule and calipers, a 12" 
steel rule or straight edge, plum bob, combination 
square, and surface gauge. 

How TO Sketch. All work on the drawing board 
should be done freehand. The T-square and tri- 
angles may be used in laying out the trimming edge 
of the plates, but for no other purpose. 

The vertical lines should be sketched as illustrated 
in Figure 5. The fingers grasping the pencil as in 
writing, control the movement entirelj'. The side 
of the hand rests upon the board, also the forearm. 
The lines are sketched downward, each one about one 
inch long, where longer lines are desired, and con- 
nected so as not to overlap. Vertical sketching is a 
finger movement. 




Figure 5 



12 



SHOP SKETCHING 




Horizontal lines are sketched as Figure 6 illus- 
trates. In this case the third and fourth fingers rest 
upon the board, as does the forearm. The lines are 
sketched from left to right, hinging at the wrist. 
This permits of drawing lines of about one inch and 
connecting them without laps for longer lines. Re- 
member, horizontal lines are drawn with a wrist 
movement, while vertical lines are drawn with a 
finger movement. Study the illustrations carefully 
and impress these methods strongly in mind. 

References : 

Crawshaw and Phillips — "Mechanical Drawing foi 

Secondary Schools." 
Phillips and Orth — "Mechanical Drawing." 
French — "Engineering Drawing." 



Figure 6 



Problems in Sketching 



Plate Layout 



Plate Layout. Tack the paper on the draw- 
ing board near the upper left hand corner. Lay out 
the trimming edges of the plate, 10".x 141^", exact, 
using the T-square and triangles to pencil in these 
lines. Now put these tools away as all the rest of 
the work will be freehand. 



Sketch the border lines in with the 4 H pencil, 
estimating 1" in from the left hand trimming line, 
and %" in from the others. Sketch these lines as 
nearly vertical and horizontal as possible. Thia 
much will be done on every jjlate of the course, and 
is termed the plate layout. 



Plate 1 



To draw the first plate, proceed as follows: 

1. Draw the horizon line 21/2" down from the 
upper border line, using the 4 H pencil for all of 
this construction work, and estimating all dimensions. 

2. Mark points in on this line for the right and 
left vanishing points }i" from the vertical border 
lines. 

3. Draw a vertical line through the center, and 
establish point A 1%" down from the horizon on this 
line. 

TTote carefully that the two vanishing points are 
on the horizon and the vertical line through the 



horizon intersects it at the level of the eye of the 
person who is viewing the perspective drawn. 

4. Estimate 1" down from A to B and sketch 
the horizontal line through this latter point. 

5. Connect A and B with the vanishing points, 
being very sure that the angle of inclination on both 
sides of AB is the same. 

6. This much of the work has been almost me- 
chanical ; now the student must estimate the distance 
between the vanishing lines that will give him the 
appearance of faces of a cube, and draw these vertical 
lines. Although the front edge AB of a 1" cube is 



14 



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16 



SHOP SKETCHING 



1", none of the remaining edges will measure true, 
since the faces are "foreshortened" as they approach 
the vanishing points. 

7. When these lines have been drawn, connect 
their upper ends with the vanishing points, as il- 
lustrated, which will enclose the remaining faces of 
the cube. 

8. If the cube appears as a true perspective, go 
over its outlines with the 2 H pencil, causing them to 
stand out from the construction lines. Eepeat with 
the border lines. 

■ 9. Complete the plate by putting in the lettering 
as indicated on the copy, omitting the "instructions" 
and the dimensions in the circles. 

You have now drawn your measuring cube, the 
basis for all future dimensions in perspective. Ee- 
member the following points : 

a. Only the front edge is in its true length. 

b. The other lines do not actually measure 1", 
but they give that appearance. 




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Figure 7 



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INSTRUCTJONS 
Copy TMia Pi^^re : FPfEEH/^r^o . 

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Plate 1 



18 



SHOP SKETCHING 



c. This is due to the "foreshortening" of lines 
as they approach the vanishing points. 

d. The level of the eye as you are observing the 
cube is above the object, hence you see the upper 
surface. If the level of the eye is below the object, 

Plate 

1. Lay out this plate as you did Plate 1. 

2. Locate point A 5" in from the right hand 
vertical border line and 2>4" down from the horizon. 
At this point sketch your measuring cube. The lines 
to the VPR are estimated the same as those to the 
VPL which is located on the drawing. 

Your problem is to sketch a pile of 108 one -inch 
cubes, 36 in a layer, three layers high. 

3. Draw two cubes directly below your measur- 
ing cube, remembering that the front edges are in 
their true length. 



you see the lower surface. If the level of the eye is 
neither above nor below, you see neither the upper 
nor the lower surfaces as- Figure 7 illustrates. 

e. In this particular kind of perspective which is 
known as 45 degree perspective, the angles of inclina- 
tion of similar lines are the same. 



4. Connect the edges with VPL. 

5. Between the upper converging lines, estimate 
the faces of six cubes. These will get smaller as tliey 
approach the vanishing point. 

6. If they appear as cubes, drop vertical lines 
through the other converging lines. 

7. Estimate the angles of inclination toward the 
right, and repeat. 

8. Complete the construction by drawing the 
lines toward the vanishing points that will give the 
upper faces of the cubes. 



PEnsPsc 77 \/£ o^ ^ p/L.£: of=^ cubes 



INSTRUCTIONS 




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Plate 2 



20 



SHOP SKETCHING 



9. Go over the outlines of the cubes with the 
2 H pencil. Omit the "instructions" and the dimen- 
sions in the circles. 



In this problem you have learned how to secure 
the measurements in perspective for any object, ex- 
amples of which will follow. 



Plate 3 



This plate represents both an orthographic and 
a perspective sketch of a small block grooved through 
the center. It is to be copied freehand, observing the 
"instructions" on the copy. 

1. Lay out the plate as before. 

2. Sketch the orthographic, using the 4 H pencil 
for all of the preliminary work. 

3. At point A, draw a measuring cube, and to 
the right and left of it draw two similar cubes, repre- 
senting a surface l"x 3"x 3". 

4. As the block is 2" high, estimate another inch 
down from the measuring cube, thus forming your 
enclosing solid for a block 2"x 3"x 3". 



5. Complete the construction of the perspective 
by drawing the groove through the center, as shown. 

6. Go over the outlines of both the orthographic 
and the perspective with the 2 H pencil, leaving the 
dimensions on the orthographic light lines. 

7. Draw a horizontal through the object for a 
table line. This will be done on all future perspec- 
tive drawings. 

In this example no vanishing points are to be 
located, the lines appearing to meet at some dis- 
tance off the drawing board. Remember that this is 
45 degree perspective and the angles of inclination 
are the same on both sides of the vertical center. 



FREEHAND SKETCH OF GROOVED BLOCK 



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3 

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OR THOGR^PHIC 



PERSPECTIVE 



INSTRUCTIONS 
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LIMES IN PERSPECTIVE . 



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Plate 3 



22 



SHOP SKETCHING 



Plate 4 



This plate involves new work in the form of an 
incompleted orthographic which is to be completed by 
the student, and lines in perspective other than 
vertical or horizontal. 

1. Lay out the plate. 

2. Sketch the orthographic as indicated, com- 
pleting it where lines are omitted. 

3. Draw the "enclosing solid" as a 3" cube. 

4. Since the upper edge of the prism comes 
exactly in the center, estimate IJ^" over from A 
and connect this point with the bottom edges by the 
means of slant lines. 

5. Complete the plate as previously instructed. 



Note that the distance toward the front edge is 
greater than the same distance toward the far side, 
since the lines are foreshortened as they approach 
the vanishing points. 

This method may be used to locate any slant lines 
in perspective. Simply draw verticals and hori- 
zontals around the slant lines, and estimate the dis- 
tances on. the verticals and horizontals. 

The half-inch dimension of the lower edge of the 
prism must be estimated on the front vertical edge 
of the enclosing solid and carried back to the point 
where needed. All horizontal measurements are 
estimated on this edge since here they are in their 
true length. 



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ORTHOGRAPHIC 



PE.P>3P£CTIVE 



INSTRUCTIONS 

Cosy THI3 PL./^T e r-p/ETEH/^hJO . 
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Or-JIT DIMeMSIOIsIS ll-J CIRCl-ES. 



PL^TE NO 



Plate 4 



24 



SHOP SKETCHING 



Plate 5 



The new work on this plate involves invisible 
edges. 

1. Lay out the plate. 

2. Sketch the orthographic, completing it where 
lines have been omitted on the copy. 

3. Draw the enclosing solid representing a block 
2i/2"x 4"x 4". Figure 8 illustrates the constructive 
lay-out. 

4. Sketch the slant lines as you did on the last 
plate, and complete the left hand and upper surfaces. 

5. Copy the invisible edges, noting that they 
follow the same principles as visible edges. 

6. Complete the plate as before. 

Invisible edges are seldom used in perspective, 
since the idea, as with the camera, is to show an 




Figure 8 

object as it would appear to a spectator. They have 
been included in this plate as a matter of practice. 



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PERSPECTIVE 



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Q WORKINe. Op_ ORTHOGRi^PHlC . SKETCH 



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Plate 5 



26 



SHOP SKETCHING 



Plate 6 



Make a working drawing and a perspective from 
some small straight line, square object assigned by the 
teacher. 

This may be a model joint, a geometrical solid, a 
block of some kind made for the purpose, or a small 
piece of furniture such as a footstool or taboret. 

Figure 9 gives suggestions as to type. 

In drawing the orthographic, sketch the views 
without taking any measurements. Estimate the 
measurements and draw the object as near to scale 
as possible. When the views are finished, put in the 
dimension lines, then the dimensions, which will be 
measured on the object with the rule. 

The Perspective Protractor 

Our previous examples have all been in 45 de- vertical touching the horizon at the level of the eye. 

gree perspective, that is, the angles of inclination of It is apparent that if the object is of irregular 

similar lines have been the same; hence the vanishing shape, much longer than it is wide or high, the 45 

points have been the same distance each side of the degree perspective will not balance up well on the 




Figure 9 



PROBLEMS IN SKETCHING 



27 



drawing. Hence we will construct a protractor that 
will be of help in solving problems involving irregu- 
lar dimensions. 




Figiire 10 



Figure 10 illustrates the "perspective protractor." 
It is constructed as follows, using the regular draw- 
ing instruments : 

On a piece of heavy drawing paper or Bristol 
board, draw the vertical and horizontal center lines. 
With their intersection as center, draw two circles, 
one 1" in diameter, and the other 3" in diameter. 
Divide the larger circle into 24 equal parts, and, by 
the means of radials, divide the smaller likewise. 
From the divisions on the smaller circle draw hori- 
zontal lines to the right and left. From the same 
divisions on the larger circle draw verticals intersect- 
ing these horizontals. The intersection of these lines, 
as shown in the lower half of the construction, will 
locate points on the curve of the ellipse. The upper 
half is drawn in the same manner. Use the irregu- 
lar curve to obtain an accurate figure. 

Erase all construction lines within the ellipse, 
and connect radials to the points located on its 
curve, as in the upper half of the construction. 

Xumber these points in degrees — starting at the 
left hand end of the horizontal center line — 15°, 



28 



SHOP SKETCHING 



30°, 45°, etc. With a sharp knife or scissors trim 
the ellipse carefully. 

Figure 11 shows the protractor in use in the 
drawing of a measuring cube. In this case the left 
hand edge makes an angle of 30 degrees with the 
horizontal, hence the right hand must be at 120 
degrees since the corner of the cube is a right angle. 
If the left hand edge had been at 15 degrees, the 
right hand would have been at 105 degrees, etc. 
When the object is square on the front corner, there 
must be 90 degrees between the two faces represent- 
ing that corner in perspective. 




„ Figuie 11 



Plate 7 



This plate involves the use of the perspective 
protractor. 

It is largely a copy plate, but, as far as possible, 
each student should be assigned a different angle for 
the perspective, 



Place the working drawing nearer the center as 
your plate will not contain the "instructions." 

The sketching of the perspective is like the previ- 
ous work with the exception of the different angles. 



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Plate 7 



30 



SHOP SKETCHING 



Note that when the angles of inclination are not 
the same, the vanishing points ^vill be at difEerent 
distances from the front corner of the object. 

Plate 8 

This plate requires no orthographic. The prob- 
lem is to make a perspective from the working sketch 
given. The long axis is to slope toward the left at 30 
degrees on the perspective protractor. 

Figure 12 is from a photograph of this joint, 
which will be of some assistance in sketching the 
perspective. 





Figure 13 

, The Circle in Perspective 

None of the previous plates have contained cir- 
cles or arcs of circles. This feature of the work will 
now be considered. 

All perspective circles are in the form of the 
ellipse. Figure 13 shows how they are formed on the 



Figure 12 



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Plate 8 



32 



SHOP SKKTCHING 



surfaces of a cube. Note carefully that the circles are 
tangent to the sides of the square faces where the 
center lines of the squares touch the outlines. This 
is apparent when the orthographic circle is considered^, 
since the circle is tangent to the square at the same 
points, Figure 14. Hence, in order to draw circles in 
perspective, enclose the circles in the orthographic 
with squares, draw the squares on the perspective with 
their center lines, and sketch in the perspective circles 
tangent at these four points. Arcs are treated in the 
same manner, though in this ease it is only part of 
the circle desired. After a little practice in this 
longer method, the student will be able to sketch in 
perspective circles and arcs without the aid of the 
squares. 




Figure 14 



the: circl-E in perspective 




INSTRUCTIONS 
Sketch thre:b . 2" cuai^s which ia^ill encuose qyljn- 

OEPS 'Si SHOiVN. COMDl-ErjC THE P!IGHT OVL^IMOEFi 

w/vp QR_s}y the : l.e f^T with the : ci p!cl./= : ij^j the : 

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PLATE NO . 

N/^r^E 



Plate 9 



34 



SHOP SKETCHING 



Plate 9 



This plate gives practice in the drawing of cir- 
cles and arcs in perspective. It represents three 
cylinders, two in the horizontal position, and one in 
the vertical. The instructions are given on the plate. 
In the horizontal position, the far side curve is 
not quite parallel with the front, but it is easily 



sketched if the far side face of the cube is put in and 
the curve made as directed before. The slight differ- 
ence is caused by the foreshortening. 

Erase all construction cubes on the finished plate, 
leaving the three cylinders with the table line. 



Plate 10 

This plate is an application of the principles holes are sometimes indicated with a note, which 



previously learned, the object being a small machine 
part. The two view orthographic and the perspective 
are both required. Notice that in a working sketch, 



gives the size as well as the method of making them — 
"drill," "bore," etc. 

The student is to copy this plate. 



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SKETCH OF BR^CK^ T 





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Plate 10 



36 



SHOP SKETCHING 



Plate 11 



This plate is a further application of the prin- 
ciples stated. Here more curved surfaces are given. 
Note that on a perspective, curves that are not sharp, 
such as filleted corners on a casting, can only be in- 



dicated with short, curved lines. The photograph. 
Figure 15, will be of help when drawing the perspec- 
tive. 




Figure 15 



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Plate 11 



38 



SHOP SKETCHING 



Plate 12 



This plate requires the completion of the top 
view in the orthographic, and a perspective sketch. 
Figure 16 will be of help in the making of this 
perspective. 



Bun the long axis to the left at an angle of 30° 
on the persj)ective protractor, since the eccentric is 
much longer than it is wide. 




Figure 16 



ECCENTRIC SHiQFT 



INSTRUCTIONS 
Complete the working dq/^wii\g 
QBsvy 6 perspeictive : sketch ih this 
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Plate 12 



40 



SHOP SKETCHING 



Plate 13 



Plate 13 is a dimensioned perspective of a buffet, 
from which a two view working sketch is required. 
This sketch must be dimensioned completely, and in- 
side construction must be indicated. The student's 
knowledge of furniture construction will be of help 
in this; also working drawings of similar types will 
make good references. 

Dimensioned perspectives are not as practical as 



working sketches, as they usually consume more time 
in the making, and it is more difficult to show inside 
construction with them. But, for small, simple pieces 
such as washers, bolts, nuts, etc., from which work- 
ing drawings will be made later, they are sometimes 
used. And again, they are used occasionally when 
explaining what is meant by a working drawing to 
a craftsman who cannot read one. 



PEPSPECT/\y£ or &UFFET 



p 



•fla 



i 



rg ETgiEliEOjZn 




INSTRUCTIONS 
pRmy fj Tv/o VIEW wcai'iNO 
SKETCf FROM THIS PEPSPeC ? 
IV £ 



PL£TE rs/O 



Plate 13 



42 



SHOP SKETCHING 



Plate 14 

This problem requires the sketching of a perspec- the plate well, as it will occupy the plate alone — the 

tive from the working sketch and the photograph, orthographic not being required. 
Figure 17. Make the sketch large enough to balance Put the dimensions on the perspective. 




Figure 17 



L^THE. P^OT 




IN5 TRUCTI OIMS 
Mi^KE ^ PERSPEC TIVE 3K£TCH OF- THE 
Oe-JEC T FROM THIS WORKING SnCTQH . PuT 
ON PRINCIP/^L PlMENSIOI\l3 . Mf^KE SKETCH 
l-i^RGE EjNCUGH TO B/^L^NCE PL^TE. 



-J 



-j-.j.. 
I 



D^TE. 



/\yjme: 



Plate 14 



44 



SHOP SKETCHING 



n 



Plate 15 

This problem is similar to the last — a dimen- 
sioned perspective alone being required. 

Note that in the side view, a full section is given 
on the plate. This is often done in working draw- 
ings since the inside construction can be more clearly 
shown. 

A section is an imaginary drawing. In this ex- 
ample, we have imagined that we have cut the piston 
on a center line through the two wrist pin bearings. 
We have then removed the front portion and drawn 
the remainder of the object. Where we have im- 
agined the saw to have cut the metal, we have drawn 
light 45 degree lines, known as "section lines." 

On future sketching plates from objects' show sec- 
tions if it will make the interior construction any 
clearer. 




Figure 18 




S«5 g/VG//V£ PISTON 



/r^ 'S TRuc riONS 
•i2SiC£ H f^^i^S PEC Ti we : sKc^rc H of the 
Piston £H<?±7 this ivorkwg Ske tcH Put 
ON ' ^RINClP i^L. PIMfiNS/ONS MflXS. S n'^TC'- i 
L^RC-E. E'\'OUO>- t TO B>^L/=ir-JC£. PUf^T.^ 



J- 2' Soae 



I 







Plate 15 



46 



SHOP SKETCHING 



Plate 16 



Make an orthographic and a perspective sketch 
of some small object selected by the teacher. Type 
suggestions are given in Figure 19. Place dimen- 
sions on the orthographic. 

When sketching from objects, take no measure- 
ments until the vievfs are sketched in. Estimate your 
proportions to scale as nearly as practical. That is, 
if you are sketching as nearly full size as possible, 
try to make your sketches show it in every view and 
every part. If the object is about 5" long, make it 
as near 5" as you can estimate, but have the length 
the same on both the top and front views. Have the 
width about the same on the top and side views. Have 
the height about the same on the front and side 
views. 

If you are reducing the object in size on the 
sketch, show this reduction evenly all the way through. 



"V\Tien the sketches have been completed — ^no 
measurements having been taken — put in the di- 
mension and extension lines. Put on the arrow 
heads, and then measure up the object. As each 
measurement is taken, put it down in its proper 
dimension line. 

When all have been completed, check it over to see 
if any dimensions have been omitted. Are the three 
dimensions given for every piece and every part? 
Are the sizes and centers of holes carefully located, 
etc.? 

Remember that in actual practice if a working 
drawing is being made from a sketch, the drafts- 
man must not take the time to go back to the object 
and measure it for missing dimensions. Every di- 
mension and every detail must be shown in the 
sketch. 



PROBLEMS IN SKETCHING 



47 




Figure 19 



48 SHOPSKETCHING 



Plate 17 

Figure 20 illustrates the body of a hanger and the front and side views, put on dimension lines, place 

it is required to make a working sketch from this the dimensions that are given, and estimate the 

figure. A few dimensions are given — just enough to others. This will give excellent practice in propor- 

secure correct proportions. The problem is to sketch tion and balance. Check your dimensions carefully. 




Figure 20 



50 



SHOP SKETCHING 



Plate 18 



Make a perspective sketch from a piece of furni- 
ture, but do not dimension it. The cabinet shop 
projects can be used as models, or the tables, benches, 
stools, cases, desks, chairs, etc., in the drawing room 
can be utilized. Each student should be assigned a 
different project as far as possible. Finish these 



perspectives carefully, using the 2 H pencil sharpened 
to a long point for the finished pencilling stage. 

A small amount of shading and graining can be 
added to this dravi^ing if desired, but do not spoil 
the effect with too much. Figure 21 is a good sug- 
gestion. 




PROBLEMS IN SKETCHING 



51 



Plate 19 



From a rather small, complicated object such 
as a valve, carburetor, etc., make a set of detailed 
orthographic sketches, and an assembly sketch. This 
luaj' require more than one sheet. If so, number 



them Plates 19-A, 19-B, 19-C, etc. 

This problem is no more difficult than a single 
object sketch, it simply requires more sketches. Each 
part should be drawn up as a single object, but the 





Figure 22 



52 



SHOP SKETCHING 



dimensions should be so carefully taken that the de- 
tailed parts will go together in the assembly with- 
out a conflict. 

Plate 20 

This final plate of the sketching course is to be 
drawn up from some machine — ^a lathe, Figure 23, 
for example — a gas engine, or any large machine. 

The character of the work on this plate will be 
determined by the amount of time left to devote to it. 

Considering the lathe as an example, one student 
might detail the headstock, another the tailstock, 
another the tool rest, a fourth the bed, etc., thus com- 
pleting a set of sketches of a large machine. Or, 
if time permits, one student could do this alone, 
other students working on other machines. 

If the instructor desires any more perspective 
sketches, these machines might serve as models for 
this advanced perspective sketching. 



Figure 22 illustrates a few of the objects suggest- 
ed for this work. 




Sketching on Cross-Section Paper 



54 



SHOP SKETCHING 



Sketching on Cross-Section Paper 



Some draftsmen prefer to make their sketches on 
cross section paper. Figure 24 illustrates such a 
sketch. This practice has a number of advantages 
over the plain paper sketch, especially if the paper 
used is ruled off in inches and subdivided into 
eights. The vertical and horizontal lines can be 
eights of an inch. The vertical and horizontal lines 
can be used to guide tlie pencil in drawing straight 
lines, and the divisions make it easy to sketch to scale. 
The main difference between this method and the 
other is that it becomes necessary to take measure- 



ments from the object as the views are drawn if the 
correct scale is to be maintained. ^ 

In this course it is recommended that a few of 
the orthographic sketches be made on cross section 
paper in order to familiarize the students with this 
procedure. 

Another ruled paper that might be of help is the 
isometric paper now on the market. By its use 
isometrics can be sketched in' place of perspectives, 
but this is not to be recommended if the ability to 
make rapid perspectives is to be acquired. 



1 : i 1 —\ 1 


III r 


L 'j 1 ■- ' — ^- 


H^fM lo tH-Ji;? - <o ! — h-2i — 1: 1 ■ ■ r 


1 „..,:.,: I ' u.L.«,.j,.; i i 


I i ir^j ■:;■ ■^■t ! i^t-i ,.,„.„.^ , j 


■H 1 r-.- iJti-^^T^^ ", — ^-TT^ijJi***^^^ jT ' it" 


y#^ 1 ii ^Sv ' 1* rr^ifTi 111 ! 1 ! 


/^' i ii.- Ji X - i ■- L-i4i. - i-il^ ^ ■ 1 .. 1 _; ! ; 


■^ > i i>^~tS-J A j-'rj'JTliJ/^ii^; :",: Jrijt ' i' 


M / l<Or TSjv' ' 1 jT- ; r r " -' -^r- ! ! ^ 




f /?N i y\\ M i ^^-^rif!/rqi-=.^ Ii 


1 f / \? '^4^ \ ■'"^ ' ; ' ' 


! 1 ij . O^H 1 «^ 1 ^L^rttNri^ 


! M 1 t i 1 N'f 1 J 1 1 i 1 r 1 i ■ 


---T h-i r-+-V- \Vi ' [A V 1 // -1 rV — h^- H- -J— '-+-H 'r^-^. ^-Ti-L-^ — i i M :- 


-^-^J C^^-^wVf^^-^''^ ' H|t-f-i-T7V-^^2rrW--Vt4- ^— 


w iV i*vN- L>ri< 1 / ! 1.. L J i.tX 1 jj ; 




1 iX^ 1 "* " 1 ^ 1 ■ i i f ' !* ' ' 


1 1 1 r^[ ' 1 ^^ ' 1 1 1 ' i 


! 1 i ^"^S* B**'*T i 11 i ! I ' 


111 Jx'' ^ "^ 1 ' i I ' 


1 ' -V^X i ' i ' 




' j ' ' i ' ffl * " ' JT j : ^; 1 1 II I ' 


! i f - -;--^J^ 1 , — -j ,-Jra -L ■ J — -1 1 ■ J-g^^ T . y M-ir+i-i-! L-L-, ! 1 , M Al 1 , i , - 


-^ ! !!i : '■ '' 'i — \ — V — 4irH: r-^-ry^z^-^w^^'^^^' i ^ 1 1 \-" — ■ — h 


111 L ^. . ..- .... f /^ \ ' ' 'frbt > 


! 1 r If,' i U^ 1 — 


1 i I .4--' ■ 1 /*'^ J 1 ' 


! 1 ,, 4 ^ Vv'liVy i "^-J-/ / 


II r;,!j --t-j- -- \^\tH| S-' 1 i T /I ^ ^ 


' i tr ! - -- V i /i 




! i 1 j 1 1 V. i ! ; 1 .'' 






1 1 i 1 ' ' k 1 / i 1 


! \ \ :__.,:• 1 \ 1 A 


1 i 1 f 1 \ •"Ts, 1^ ; ■ 


\ ' \ i i \ f i y ' 


! i 1 1 i i ! ^(k ! W' J i/ i 


1 M i ■ 1 1 L 4. \ i > jV / ! ' 


II 1 i 1 1 — .^f- ^^ -Ir IT ' < ■ 


Mill ^* i i ■ 1 , \t^ ij^ i 


1 1 1 i „ ^^ ^^X-*^ 1 


1 r j ■ ! i w' ~r 


1 i ! i ' ■ i M- |r»^.^^-t^ 1 ■ ! 


! i a L i i 14 . J ^ i , . i 


; yi'/ rA/7v^-Oi -.^frt i^'6n ^ ja./M%oni^'.^ip-\ "2 "^ 


1 i 1 M 1 i ill 1 


_Ji,.,. M 1. 1 1 1 1 .III 1 



Figure 24 



56 



SHOP SKETCHING 



Supplementary Problems 



The following plates have been added to sup- 
plement the course. They may be used in a number 
of ways. They may serve as additional plates for the 
more apt students to work upon while the slower are 
catching up; they may serve as regular plates in 



longer courses such as might be given in trade or 
normal schools; or they may be used to make 
regular mechanical machine drawings for the ma- 
chine drawing courses. 



Supplementary Plate 1 



This plate represents a test plate to follow regu- 
lar plate 6. It contains less instructive material than 
the plates preceding, hence the students must use 
more initiative to work it out. No instruction should 



be given concerning it, and students should not be 
allowed to visit with each other nor look at each 
other's work while solving it. 



GROOVED BLOCK 



INSTRUC T!C!NS 
CO/^^L E rs THE -TOP WHVy 

Th±3 .Sf^jsss.- 



•6 



P- 



I 

■vl 



Supplementary Plate 1 



58 SHOPSKETCHING 



Supplementary Plate 2 

This plate represents two small machine parts in sketch and a copy of the perspective can be required 

dimensioned perspective. Its use may be restricted of each piece, 

to the drawing of working sketches, or a working 



PRILL Block 



T BLOCK 





Supplementary Plate 2 



60 



SHOP SKETCHING 



Supplementary Plate 3 



A working sketch of a special wrench is illus- 
trated on this plate. One feature is a revolved sec- 
tion — a section at right angles to the center line at 
any chosen point to show the shape of the object at 
that point. A revolved section is often used to il- 
lustrate the shape of the spokes in fly-wheels and 



pulleys, and is sometimes drawn on the object itself 
rather than to the side as illustrated. 

The problem in sketching is to make a perspec- 
tive from this working sketch, or to make a similar 
sketch from a wrench furnished by the teacher. 



SPECML WRENCH 









V 1 






/ 


,-/o 


'a 


.IS 


■7 O 


'ifo 

'" 1 


^^>-i= 


i 




'^l& 


a ' 


y-ir 


r 

! 


11 


* 







nT /^ 1 1 


^-v 





T 
L 




-i-« 



T 



Supplementary Plate 3 



62 SHOP SKETCHING 



Supplementary Plate 4 

Plate 4 illustrates two working sketches, one of a it being imaginea that a part of the object has been 

clamp handle such as is sometimes used to tighten broken away in order to show the threads. This is 

the tail stock of a wood lathe, and the other an S called a "partial section." 

wrenc . j^ jg suggested that perspectives be required of 

The clamp handle shows scre'w threads in section, these objects. 



WRENCH 



CL/3MP HANDLE. 





Supplementary Plate 4 



64 SHOPSKETCHING 



Supplementary Plate 5 

Many good problems in sketching can be secured sketches can be made from these perspectives, or 

in the wood shop. The footstool and taboret are similar sketches can be made from the working draw- 

very familiar objects to most students. "Working ings which the cabinet shop will have in abundance. 




T/^&OKET 



roQ-rs-rooi^ 




\ 



^l 



N 



>i 



■"N 






.15' 





Supplementary Plate 5 



66 



SHOP SKETCHING 



Supplementary Plate 6 



The working sketch of a tumbling shaft bracket 
is a good example of a simple bearing. Notice that 
on the front view two full circles are represented, 
the large one being the hole bored out in the body 
of the bracket, and the small one the inside bearing 
suiface of the bushing which is driven or pressed in 



place. An oil liole tlirough both the bearing and the 
bushing allow lubrication for the shaft which move:3 
back and forth in the bearing. 

A perspective from this working sketch is the 
required ijrobleni in this case. 



TUMBLING SH/^rr BR/^CKC; 







. Pfl't-L. ro.-^ 14:" SDLTS 



U- 



- 3S- 



■-^ 



;,-i & v y»-4=^— -^ »'^ 



^ 



•T^TT^^^r 



--■ 3; 



Supplementary Plate 6 



68 SHOP SKETCHING 



Supplementary Plate 7 

This dimensioned perspective shows a valve yoke of it. Notice the manner of showing the curved 

such as is used on most types of locomotives. A edges in perspective, 

working sketch, completely dimensioned, is required 



\MIA/E YOKE 




WROUGHT IRON 



Supplementary Plate 7 



70 



SHOP SKETCHING 



Supplementary Plate 8 



This bearing shows two views in full section. 
When it is necessary, any number of sections can be 
used to illustrate, clearly, the internal construction 
of a piece. A large object with many holes inside. 



such as the cylinder block of a gas engine, may re- 
quire at least a dozen sections, taken through various 
parts of the body. 

A perspective sliould be made of this project. 



Q/3E &OPy SIDE BE^RIN e FOR UP RErR. C£R3 




M,<iL.i.Ef^BLE. IRON 



..J 



Supplementary Plate 8 



72 



SHOP SKETCHING 



Supplementary Plate 9 



It will be very good practice for the student to 
trace out the meaning of the various dotted lines on 
this working sketch. As his ijroblem, and to test his 
ability to read working drawings, the student should 



copy the top view and draw full sections in place of 
the front and side views as they are here given. 

A perspective from this working drawing will 
also prove of value to the student. 



^'^ 



ip ia < 



r 



(OIT 



Oils 



O 



-'■0 



^Q'»V^.P CORNER POgT 

.SHOE FOR qoizoorqo 

TON RETRieErRf^TCQ 



I"t= 



_i_ 






kS 






N-Ii, 



T' 



H-3^--J 



U- 



IT 



r -L 



irn$ 



A-o 



I , i 






U^^-^-^ 



J_ 









l£--! 




rii 



3 Pii'l^ CfW 



CTHf£f^\/VISE .SHOIVN 



Supplementary Plate 9 



74 



SHOP SKETCHING 



Supplementary Plate 10 



If a perspective of this bracket is drawn, notice 
that there are two bearings, the one to the left being 
the same distance from the center line that the one 
to the right is drawn. This is often done in work- 
ing drawings when the object is long, and the parts 



on each side of the center line are the same. There 
is always one dimension which covers the entire 
length of the iinished piece. The dimension 32^2" 
represents it here, and there is no arrow head on its 
left hand end. 



r^OTJON nop HUNGER BRACKET' 



WROT IRON a u.'jH 




-^ 






H- 

(VJ 




I, ii : ii ' T! I 

1 > I T, ! 



5;- 




CfJST IRON 



Supplementary Plate 10 



76 



SHOP SKETCHING 



Supplementary Plate 11 



The last three plates represent projects of interest 
to agricultural and architectural students. 

In the first the perspective of a watering trough 
is given. The principal dimensions are attached. 



The ability to make such sketches will be appreciated 
by the farmer who very often is called upon to ex- 
jDlain some part of his farm equipment to another 
person who is to build it for him. 



CONCRETE WATERING TPfOUOH 




Bo-TTOr^-l <3" TJ-4ICK 



Supplementary Plate 11 



78 SHOP SKETCHING 



Supplementary Plate 12 

The perspective of an ordinary window frame is head, stile, and sill, dimensioning the parts in the 

shown en this plate. regular manner. 

The student should draw sections through the 



UJih{DGyj F-fi.iq[v1Er 







•'"4 





'DLir^P 3J0P H, Xl| 



puLLEry oyiLt H x^l 



•?TT'^^ 570P ix| 



51LL l|x&| 



Supplementary Plate 12 



80 



SHOP SKETCHING 



Supplementary Plate 13 



The problem presented on this plate is an inter- 
esting one to the student of agriculture. After solv- 
ing it and putting on its principal dimensions, he 
should have acquired the ability to make working 
sketches of simple structures of this type. If a 
neighbor owns a hog pen which the student's father 



wishes to duplicate on his farm^ it will be a very use- 
ful procedure for the student to measure up and 
sketch the hog pen in such shape that the building 
can -be built from his sketches without the need of 
further reference to the existing building. 



CHIOKEJN HOUSE 




'r;%^;;!-l-'ffl| i .^ pfi sr* if 




as jLiieH^-fe? 



pi--k'..°' pE^CTiV7r 




IN5T QUCTiON5 

O/^ T/i'/.S CHICKS^/ ^lOUSg. A'o 0//vf - 



l^i^f^ pk/5ri 



Supplementary Plate 13 



INDEX 



Page 

Angle of Inclination 14 

Board S 

Calipers 11 

Circle in Perspective 30 

Contents 3 

Cross-Section Paper 54 

Definitions 7 

Drawing Materials 8 

Enclosing Solid 20 

Erasers 8 

Foreshortening 16 

Forty-five degree Perspective 18 

Horizon Line 14 

Horizontal Sketching 12 

How to Sketch 11 

Index S3 

Inventive Sketches 7 

Measuring Tools 11 

Paper 8 

Pencils 8 

Perspective Protractor 26 

Plate Layout 14 

Plate 1 14 

Plate 2 18 

Plate 3 20 

Plate 4 22 

Plate 5 24 

Plate 6 26 

Plate 7 28 

Plate 8 30 

Plate 9 34 

Plate 10 34 

Plate 11 36 

Plate 12 38 



Page 

Plate 13 40 

Plate 14 42 

Plate 15 44 

Plate 16 46 

Plate 17 48 

Plate 18 50 

Plate 19 51 

Plate 20 52 

Plumb Bob 11 

Preface 5 

References 12 

Rule 11 

Section 44 

Shop Sketching 7 

Supplementary Plate 1 56 

Supplementary Plate 2 58 

Supplementary Plate 3 60 

Supplementary Plate 4 02 

Supplementary Plate 5 64 

Supplementary Plate 6 66 

Supplementary Plate 7 68 

Supplementary Plate 8 70 

Supplementary Plate 9 72 

Supplementary Plate 10 74 

Supplementary Plate 11 76 

Supplementary Plate 12 78 

Supplementary Plate 13 80 

Square 11 

Surface Gauge 11 

Table Line 20 

Test Plate 56 

Vanishing Points 14 

Vertical' Sketching 11 

Working Sketches 7 



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